Car-brake regulator



`(No Model.) l

W. C. PARNUM.

GAR BRAKE'. REGULATOR.

No. 468,562. Patentedrf'eb. 9, 1892Ki Wzrzs S e@ z Nrrn ATENT OFFICE,

VILLIAM O. FARNUM, OF ARLINGTON, VERMONT.

CAR-BRAKE REG U LATO R.

SPECIFICATION forming part of Letters Patent No. 468,562, dated February9, 1892. Application iled March 16J 1891. Serial No. 385.165. (Nomodel.)

To @ZZ whom t my concern:

Be it known that I, WILLIAM C. FARNUM, a citizen of the United States,residing at Arlington, in the county of Bennington and State of Vermont,have invented a new and useful Improvement in Car-Brake Regulators, ofwhich the following is a specification.

My invention relates to devices for limiting the amount of pressureexerted by the brakeshoe upon the wheel of the car or other vehicle towhich the brake is applied.

The object of my invention is to provide a device of a simple, durable,and efficient construction which will operate to automatically controlor regulate the amount of pressure or force transmitted from thehand-wheel, aircylinder, or other source of power to the brake, whichmay be readily and easily applied to any form of brake mechanism now inuse, and which will operate equally well and without requiring specialadjustment throughout all ordinary changes in the adjustment of thebrake mechanism itself from wear, &c.

To this end my invention consists, in connection with the brakemechanism and its pull or power transmitting-rod, of a stop rod or barsecured rigidly to the frame-work of the car or car-truck, or oth ervehicle, and a clamp adapted normally to slide freely on the stoprod,and furnished with a spring adapted to withstand the normal strainwithoutcompresn sion, the compression of which when the strain exceedsthe normal amount causes the clamp to bite or become fixed to thestop-rod, and thus prevent the transmission of extra force t0 thebrake-shoe, while at the same time the brake is continually held appliedwith the normal or proper amount of force. The stop-rod is made longenough to accommodate all varying conditions of wear and adjustments ofthe brake mechanism, so that no special ad justment either of my deviceor of the brake mechanism with which it. is combined is necessary.

My invention further consists, in connection with a brake and brake-rod,stop-bar, and spring, of a clamp consisting of two levers pivotedtogether and furnished with sockets adapted to slide on the stopbar whenthe levers are held in their normal position by the spring between them,but which, or one of which, bites the stop-bar when the springcompresses.

My invention also consists in the novel de- 'vices and novelcombinations of parts and devices herein shown and described, and moreparticularly pointed out in the claims.

In the drawings, which form apart of this specification, and in whichsimilar letters of 'reference indicate like parts, Figure 1 is a sideelevation of -a device embodying my invention, showing part of one endof a railwaycar., Fig. 2 is enlarged side elevation. Fig. 3 is avertical section, and Fig. 4 is a crosssection, on line 4 4 of Fig. 2.Fig. 5 is the stop-bar provided with ratchetteeth.

In the drawings, A represents a portion of the framework of the car ortruck; B, the wheels; C, brake-shoes; D, the brake-beams; E, thebrake-levers, and F the brake rod or connection between the brake-leverand thc windlass or other source of power.

In the drawings the source G of power is, for convenience, representedas being an ordinary hand brake or windlass.

H is the stop barorrod,secured rigidly and firmly to the frame-work A.On the stop-bar H is a reciprocating or sliding dog or clamp K K', whichis adapted, when the two parts K K are held in their normal relation toeach other or to the stop-bar, to slide freely on the stop-bar Ilwithout biting or engaging the same, but which when the 4 parts K K aremoved out of their normal relation to each other or to the stop-bar toclamp, bite, or engage the stop-bar and thus prevent the transmission ofany further power to the brakeshoe. A spring L, preferably a coiledspring and surrounding the stop-bar Il, holds the twoparts of the clampK K in their normal relation to each other and to the stopbar. Thisspring L is of such strength as to withstand the normal strain or forcedesired to be transmitted to the brake-lever Without compression. Theclamp K K is inserted in the brake connection F, leading from the sourceof power to the brake-lever, so that the force transmitted acts againstthe spring L, which holds or tends to hold the two parts of the clamp intheir normal position or relation to each other and to the stop-bar. Theclamp IOO soI

K K may of course be of any suitable form or construction known to thoseskilled in the art, and adapted to have the operation and perform thefunction set forth in my combination; but I prefer to construct theclamp as follows, and herein my improvement in part consists: Each partK K of the clamp consists of a lever, the same being pivoted together atr. The levers K K are furnished with sockets or holes 7.o k2, adapted tofit and slide on the stoprod H. The levers are further furnished withbosses or shoulders 7c3 to receive the opposite ends of the coiledspring L, which fits between the two ends of the levers. The levers K Kare connected by slotted links ff with the brake rod or connection F,and pins f2, secured to the levers K K and tting in the slots f3 of thelinks ff', limit the extent the levers K K can be separated by thespring L. The socket or hole 7a2 in the lever K may preferably-berounded, as shown in the drawings at Figs. 2 and 3, so that only thelever K will bite or engage the stop-bar H when the spring L compresses.

The operation is as follows: Whenless than the normal or maximum amountof force desired is being exerted or transmitted to the brake-lever, thet-wo clamp-levers K K will 'remain in their normal position in respectto each other and to the stop-bar H-that is to say, at right angles tothe stop-bar, as shown in Figs. l and 2-and thus slide freely back andforth on the stop-bar as the rod or connect-ion F is drawn up orreleased in the ordinary operation of the brakes. The moment, however,more than the normal or maximum amount of force is exerted by the sourceof power upon the rod or connection F the spring L will begin tocompress, thus causing the pivoted levers K K to be drawn together, asindicated in Fig. 3, and the levers rocked or tilted out of theirright-angle relation to the stop-bar H, so that the ciamp-socket la ofthe lever K will bite or engage the stop-bar H, and thus fix theclamprigidly to the stop-bar and prevent the transmission of any furtherpower to the brake-lever, while at the same time the brake-shoe isconstantly held applied to the wheel with the required or proper amountof pressure. By this means the full efficiency of the brakes is secured,while at the same time the injury to thewheels by sliding or spottingthe same on the track is prevented, and no changing or adjustment of thebrake mechanism is required. It is preferable to make the bar H smooth.It desired, it may be roughened or furnished with ratchet-teeth, .asindicated in Fig. 5.

I claiml. In a brake, the device for regulating or Weighing the amountof pressure exerted by the brake-shoe, consisting in the combination,with a brake and its power-transmitting rod or connection, of a stop-barand a clamp inserted in said brake connection, adapted normally to slideback and forth freely on said stop-bar, said clamp being furnished witha spring adapted to yield under an abnormal strain, and thus cause saidclamp to bite or engage the stop-bar, and thereby prevent thetransmission of an abnormal force or pressure to the brake-shoe, whileat the same time the brake is held applied, substantially as speciiied.

2. The combination, with a brake mechanism, of its power-transmittingrod or connection, a stop-bar, and a dog or clamp adapted to slide backand forth freely on said stopbar normally and to bite or engage saidstopbar when an abnormal force or strain is exe'rted, and a device forholding said clamp normally in its free or sliding position,substantially as specified.

3. The combination, in a brake, of a power# transmitting rod orconnection F with a stop# bar H and a pair of clamp-levers K K', pivotedtogether and furnished with sockets adapted to fit and slide on saidstop-bar, and a spring L, substantially as specified.

4. The combination of brake connection F with stop-bar H, clamp-levers KK', and spring L, substantially as specified.

5. The combination of brake connection F with stop-bar II, clamp-leversK K spring L, and slotted connecting-links f f substantially asspecified.

G. The combination of brake connection F with stop-bar H, clamp-levers KK spring L, and slotted connecting-links ff', said levers K K beingfurnished with stop-pins 7a3, substantially as specified.

7. The combination, with brake connection F, of stop-bar H, pivotedclamp-levers K K', having sockets fitting on said stop-bar, and springL, one of said clamp-levers having a rounded or curved socket, so thatit will not bite or engage the stop-bar when the spring yields,substantially as specified.

8. The combination, with stop-bar H, of pivoted clamp-levers K K andspring L, substantially as specified.

WILLIAM C. FARNUM.

Witnesses:

H. M. MUNDAY, EDMUND ADcocK.

IOO

